Maximum Power Rating of SMPS

[sundar-edaboard]

Dear all,


How to measure the maximum power rating of a SMPS power supply having 5V and 12V Output?

Regards,
Sundar.A

 

[schmitt trigger]

5v times its output current
12v times its output current
Add the two power values.

 

[BradtheRad]

The everyday way to measure power is to connect various resistance loads. Measure the volts and amps delivered. Notice that maximum power is not always achieved at maximum volts, nor is maximum power always achieved at maximum amperes.

Since you have two fixed voltages, you should test the total power when (a) both are powering loads, and (b) test them individually without the other being connected.

There is the maximum power rating which is determined by typical failure modes, brought on by (a) overheated components, or (b) overstressed components.

There is the instantaneous power rating, and there is the continuous power rating.

But since the question is about a SMPS...

Maximum power is determined by how many amperes you can get going through the inductor, as you charge and discharge it. If you operate it outside of its specs, it will overheat, or it will saturate, etc.